Fertility and reproductive choice in women with HIV-1 infection

OBJECTIVE

To measure fertility and birth rates and to describe the reproductive histories of women diagnosed with HIV-1 infection in Australia.

METHODS

The medical records of 294 women with HIV-1 infection in four states of Australia were reviewed. Expected fertility and birth rates were calculated using national statistics.

RESULTS

In the study population, 152 (52%) women had at least one pregnancy prior or subsequent to HIV-1 diagnosis. At maternal HIV-1 diagnosis, 71 (24%) women had a total of 106 children aged under 15 years. During the study period, 246 women were aged 15, 44 years and 58 (23%) of these became pregnant after HIV-1 diagnosis. Women whose exposure to HIV-1 was injecting drug use were twice as likely to become pregnant and more likely to have multiple pregnancies than women who did not report injecting drug use. The annual general fertility rate was 30 per 10,000 compared with 63 per 10,000 for the Australian female population aged 15-44 years, and the birth rate in women with HIV-1 infection was one-half that of the general female population. Of pregnancies confirmed after HIV-1 diagnosis, 47% were voluntarily terminated, a rate more than double that of the general population. All multiple terminations were among women whose exposure to HIV-1 was injecting drug use.

CONCLUSIONS

Fertility and birth rates among women with HIV-1 infection are lower than the general population and the rate of termination higher. The results of this study provide a basis for the management of women with HIV-1 infection who are considering pregnancy.

Nonlinear mixed effects modeling of single dose and multiple dose data for an immediate release (IR) and a controlled release (CR) dosage form of alprazolam

PURPOSE

NONMEM was applied to single dose and multiple dose bioavailability data for an immediate release (IR) and a controlled release (CR) dosage form of alprazolam to acquire additional information from the data which are not easily obtainable by traditional means.

METHODS

The objective function value (OBJ) and diagnostic plots were used as measures of goodness of fit of the model to the data. A change in the OBJ value of 7.9 was necessary to show statistical significance (p < 0.005) between two models when the two models differed by 1 parameter.

RESULTS

A two-compartment linear model with first-order absorption and elimination best describes the data. Including a lag time, two different rates of absorption (KAIR and KACR), and bioavailability for the CR relative to the IR dosage form significantly improved the fit of the model to the data. Cigarette smoking was associated with a 100% increase in clearance of alprazolam as compared to non-smokers. The higher residual variability observed in this study, where interoccasion variability (IOV) was not initially modeled, could be explained to a large extent by the presence of significant interoccasion variability (IOV).

CONCLUSIONS

Since alprazolam has been suggested to be mainly metabolized by the CYP3A4 isozyme in humans, it appears that tobacco could be an inducer of CYP3A4 and/or alprazolam may be metabolized by other isozyme(s) (specifically, CYP1A1/1A2) that are induced by cigarette smoke. The population pharmacokinetic model approach combined with exploratory graphical data analysis is capable of identifying important covariates from well-controlled "data rich" Phase I studies early in drug development.

SOX9 binds DNA, activates transcription, and coexpresses with type II collagen during chondrogenesis in the mouse

Two lines of evidence suggest that the Sry-related gene Sox9 is important for chondrogenesis in mammalian embryos. Sox9 mRNA is expressed in chondrogenic condensations in mice, and mutations in human SOX9 are known to cause skeletal dysplasia. We show here that mouse SOX9 protein is able to bind to a SOX/SRY consensus motif in DNA and contains a modular transcriptional activation domain, consistent with a role for SOX9 as a transcription factor acting on genes involved in cartilage development. One such gene is Col2a1, which encodes type II collagen, the major structural component of cartilage. We have compared, in detail, the expression of Sox9 and Col2a1 during mouse development. In chondrogenic tissues the expression profiles of the two genes were remarkably similar. Coexpression was detected in some nonchondrogenic tissues such as the notochord, otic vesicle, and neural tube, but others such as heart and lung differed in their expression of the two genes. Immunohistochemistry using an antibody specific for SOX9 revealed that expression of SOX9 protein mirrored the distribution of Sox9 mRNA. Our results suggest that SOX9 protein is involved in the regulation of Col2a1 during chondrogenesis, but that this regulation is likely to depend on additional cofactors.

In vivo analysis of DNA-protein interactions on the human erythropoietin enhancer

The erythropoietin (EPO) gene is one of the best examples of a mammalian gene controlled by oxygen tension. The DNA elements responsible for hypoxia-induced transcription consist of a short region of the proximal promoter and a <50-bp 3' enhancer. The elements act cooperatively to increase the transcriptional initiation rate approximately 100-fold in response to low oxygen tension in Hep3B cells. Two distinct types of transactivating proteins have been demonstrated to bind the response elements in the human EPO enhancer in vitro: one shows hypoxia-inducible DNA binding activity, while the other activity binds DNA under normoxic and hypoxic conditions. We have investigated the DNA-protein interactions on the human EPO enhancer in living tissue culture cells that produce EPO in a regulated fashion (Hep3B) and in cells that do not express EPO under any conditions tested (HeLa). We have identified in vivo DNA-protein interactions on the control elements in the human EPO enhancer by ligation-mediated PCR technology. We show that the putative protein binding sites in the EPO enhancer are occupied in vivo under conditions of normoxia, hypoxia, and cobalt exposure in EPO-producing cells. These sites are not occupied in cells that do not produce EPO. We also provide evidence for a conformational change in the topography of the EPO enhancer in response to hypoxia and cobalt exposure.

[Vascular protection with estrogen. In-vitro and in-vivo effects--mechanisms and clinical implication]

Myocardial infarction is the major cause of death in the western world. Men are more prone to develop coronary artery disease than women of the same age, in whom coronary disease is rare before menopause. Epidemiological data have shown that estrogens are vasoprotective--especially in the coronary circulation--but the underlying mechanisms have been investigated more thoroughly only in recent years. Only up to half of the protective effect of estrogen replacement therapy an be attributed to its positive effects of the lipid profile. However, a large part of this protection is caused by mechanisms distinct from lipid metabolism. It is now known that estrogens also exert effects on vascular function and structure of the vessel wall involving numerous cellular and molecular mechanisms. Actions of natural estrogens on human vascular cells and arteries will be discussed. Estrogens modulate vascular function by increasing nitric oxide production via stimulation of endothelial nitric oxide synthase (eNOS) and decreasing endothelin-1 levels in vivo. Furthermore, 17-beta estradiol is a potent inhibitor of vascular smooth muscle cell proliferation and migration, which play a major role in atherosclerotic vascular disease and in the remodeling process. 17-beta estradiol also acutely affects vascular tone in human arteries and attenuates constriction induced by contractile agonists. Finally, clinical studies showed that 17-beta estradiol can acutely and chronically ameliorate vascular function in women with and without vascular disease. In conclusion, results from clinical and in vitro studies showed positive effects of natural estrogens on vascular function which could explain in part their protective actions against coronary heart disease. Thus, primary prevention of coronary heart disease by estrogen replacement therapy after menopause appears to be a new approach to reduce cardiovascular mortality in women.

Paternal X-chromosome inactivation in human trophoblastic cells

Dosage compensation for X-chromosome-linked genes between male and female mammals occurs by inactivation of one of the two X chromosomes in the female. In somatic cells, either the paternal or the maternal X chromosome is randomly inactivated in a given cell. In contrast, in the extra-embryonic tissues of mice, the paternally-derived X chromosome is preferentially inactivated. The evidence for paternal X-chromosome inactivation in humans is controversial and remains to be clarified. In this study, we have developed a sensitive polymerase chain reaction (PCR) technique to investigate the methylation pattern of the X-linked androgen receptor (AR) gene. The 5' CpG island of this gene is methylated on the inactive X chromosome and hypomethylated on the active X chromosome in somatic cells. The paternal and the maternal alleles of the AR gene may be distinguished by a polymorphism in the number of CAG triplet repeats within the CpG island. As a source of human extra-embryonic tissue, we used chorionic villus (CV) samples from female conceptuses of 10-12 weeks gestation. From a tiny branch of a CV sample, two distinct cell lineages, the trophoblastic and mesodermal lineages, were dissected apart by trypsin digestion and micromanipulation and DNA was extracted separately from these purified tissues. Digestion of the DNA with the methylation-sensitive restriction enzyme, Hpall, followed by PCR amplification revealed that the paternal allele is preferentially methylated in trophoblastic cells, but not in mesodermal cells. These results strongly suggest that the paternal X chromosome is preferentially inactivated in the human extra-embryonic tissues early in development.

Extracolonic features of familial adenomatous polyposis in patients with sporadic colorectal cancer

We have investigated the occurrence of attenuated extracolonic manifestations (AEMs) of familial adenomatous polyposis (FAP) in patients with non-polyposis colorectal cancer. In a prospective case-control study, we observed that significantly more colorectal cancer patients exhibited AEM than did age and sex-matched controls (19.5% vs 7.5%, P < 0.004). However patients with AEMs do not have occult FAP, as we found no heterozygous adenomatous polyposis coli (APC) gene mutations despite extensive analysis of constitutional DNA. Genome-wide DNA replication errors (RERs) occur in a proportion of colorectal cancers, particularly right-sided lesions and in almost all tumours from hereditary non-polyposis colorectal cancer (HNPCC) patients. As AEMs have been reported in familial colon cancer cases, we investigated the relationship of AEMs to tumour RER phenotype. There was indeed an excess of AEMs in patients with right-sided tumours (30.2% of 53 patients vs 14.7% of 116 patients, P < 0.03) and in those with RER tumours (3 out of 12 patients with RER tumours vs none out of 21 patients with non-RER tumours, P < 0.05). Two patients with AEM were from HNPCC families compared with none of those without AEM (P < 0.05). The association of AEMs with colorectal cancer is intriguing, and we speculate that it may be a manifestation of mutational mosaicism of the APC gene, perhaps associated with a constitutional defect in DNA mismatch pair.

Assessing children with traumatic brain injury during rehabilitation: promoting school and community reentry

Children with traumatic brain injuries (TBI) require a comprehensive, multidisciplinary evaluation during rehabilitation to promote recovery and to facilitate a smooth transition to home and school. This article summarizes the common consequences of TBI and reviews a process-oriented approach to assessing children with moderate to severe TBI during rehabilitation. An emphasis is placed on early and regular communication among rehabilitation specialists, family members, and educators. Such collaboration permits clear identification of functional abilities and increases the child's potential for a positive long-term outcome.

Pattern of growth in children with cerebral palsy

OBJECTIVE

To provide a growth reference standard for children with quadriplegic cerebral palsy (QCP). Growth references specific to children with cerebral palsy would facilitate uniformity in clinical appraisal of their growth and nutritional status and would simplify comparative interpretation of growth data.

DESIGN

Weights and lengths were obtained according to standardized procedures. Measurements were taken at time of visit to an orthopedic clinic and from retrospective review of charts.

SUBJECTS

Three hundred sixty children with QCP. Growth data were based on 1,630 observations.

ANALYSIS

Growth curves representing the 10th, 50th, and 90th percentiles were estimated using a smoothing splines technique. Statistical bootstrapping was performed to confirm significant differences from the growth charts of the National Center for Health Statistics (NCHS).

RESULTS

Growth charts were constructed for boys and girls, aged 0 to 120 months, depicting length for age, weight for age, and weight for length. Average differences in length for age, weight for age, and weight for length between children with QCP and NCHS standards were -2.3 z, -2.4 z, -1.3 z for boys, and -2.1 z, -2.1 z, -1.1 z for girls. Children with QCP fell progressively behind in stature and weight. Compared with their NCHS counterparts, they were 5% shorter at 2 years of age and more than 10% shorter at 8 years of age.

APPLICATION

Charts representing the pattern of growth in children with QCP should be accessible to parents and health care professionals to facilitate evaluation and monitoring of nutritional status.

Cholesterol levels in normal Irish adults: the Mater Hospital Cholesterol Screening Survey

Serum samples from 954 Irish adults (604 males, 350 females) aged 18 to 65 years were analyzed within 24 hours of receipt for non-fasting total serum cholesterol levels. The subjects were volunteer blood donors (Blood Transfusion Service Board, Pelican House, Dublin) presenting from June 1990 to February 1991. Serum cholesterol increased significantly with age in both males and females. Mean serum cholesterol in males increased from 4.5 (+/- 0.9) mmol/l in those < 25 years, to 5.7 (+/- 1.0) mmol/l at age 55-64 years. In females, mean serum cholesterol increased from 4.3 (+/- 0.9) mmol/l less than 25 years to 6.2 (+/- 0.8) mmol/l at age 55-64 years. Options for reporting cholesterol ranges are discussed. The overall mean cholesterol concentration of 5.1 mmol/l seen in this study is lower than that reported for comparable studies of U.K. and American subjects, but higher than observed in Japanese individuals. Almost 48% of the studied population had a serum cholesterol value less than 5 mmol/l and over 56% had levels less than 5.2 mmol/l.

Exclusion of Sox9 as a candidate for the mouse mutant tail-short

The Sry-related gene Sox9 has been proposed as the gene responsible for the mouse skeletal mutant Tail-short (Ts), on the basis of its expression in skeletogenic mesenchymal condensations in the mouse embryo and its chromosomal location in the region of Ts on distal Chromosome (Chr) 11. We present here detailed mapping of Ts locus relative to the Sox9, using an intersubspecific cross. Among 521 backcross progeny, 16 recombinants were detected between Sox9 and Ts, suggesting a separation of 3.5 +/- 0.01 cM, and excluding Sox9 as a candidate for Ts. A further nine recombinants were detected between Ts and the polycomb-like gene M33, suggesting that these loci are separated by 1.8 +/- 0.011 cM. Six microsatellite markers were co-localized to the Ts locus, providing reagents for positional cloning of Ts.

Response of families to two preventive intervention strategies: long-term differences in behavior and attitude change

OBJECTIVE

To explore the long-term impact of two forms of preventive intervention designed to diminish risk to children in families in which one or both parents suffered from affective disorder.

METHOD

Fifty-four parents in 18 families were initially assessed and randomly assigned to one of two interventions--a clinician-facilitated, manual-based, psychoeducational preventive intervention or a standardized lecture-group discussion in which similar educational information was presented. Assessments included standard diagnostic interviews, child behavior scales, and semistructured interviews with parents about the effects of the intervention. Follow-up assessments were conducted three times over the 3-year follow-up interval.

RESULTS

No harmful effects were reported for either intervention, and ratings of degree of upset about reported concerns declined across time for both conditions. Families receiving the clinician-facilitated intervention reported more behavior and attitude changes than did lecture-group families when assessed after intervention. The difference between the two groups was sustained at further follow-up assessments.

CONCLUSION

Although both preventive interventions produced changes in behaviors and attitudes, parents in the clinician-facilitated intervention reported more benefit. These data support the hypothesis that linking cognitive information to the family's life experience produces long-term changes.

A polymorphic and hypervariable locus in the pseudoautosomal region of the CBA/H mouse sex chromosomes

We have identified a genomic locus (DXYH1) that is polymorphic and hypervariable within the CBA/H colony. Using a panel of C57BL/6 x Mus spretus backcross offspring, it was mapped to the distal end of the X chromosome. Pseudoautosomal inheritance was demonstrated through three generations of CBA/H x CBA/H and CBA/H x C57BL/6 crosses and confirmed through linkage to the Sxr locus in X/Y Sxr x 3H1 crosses. Meiotic recombination frequencies place DXYH1 similar 28% into the pseudoautosomal region from the boundary. The de novo generation of CBA/H variant DXYH1 restriction fragment length polymorphisms during spermatogenesis is suggestive of the germline instability associated with hypermutable human minisatellites. The absence of DXYH1-related sequences in Mus spretus provides DNA sequence evidence to support the observed failure of X-Y pairing during meiosis and consequent hybrid infertility in C57BL/6 x Mus spretus male F1 offspring.

Eye patch treatment for the pain of corneal abrasion

The traditional use of patching and topical antibiotics in the treatment of corneal abrasion has recently been challenged, particularly after foreign body removal. In a prospective, controlled, randomized study of 33 patients treated in the emergency department for eye pain and corneal abrasion, we attempted to determine whether eye patching affected the pain of simple corneal abrasions. After fluorescein examination with magnification (x 5), a visual analog pain score was recorded and the patient was randomized to either the patched or nonpatched group. A standard analgesic was supplied, and all patients had follow-up at 24 hours, when repeat pain scores and analgesic use were recorded. The groups were compared by using the Wilcoxon's rank sum test, Student's t test, and analysis of covariance as required. There was no significant difference in the mean changes in pain scores between the patched and nonpatched groups. Analgesic use was also similar. We conclude that routine eye patching does not favorably affect the pain associated with the treatment of simple corneal abrasion.

Co-amplification to tail-to-tail copies of MuRVY and IAPE retroviral genomes on the Mus musculus Y chromosome

We have isolated a clone from a C57BL/6 genomic library that contains both part of the Y Chromosome-specific 8.7 kbp MuRVY genome (Hutchinson and Eicher, J. Virol. 63, 4043, 1989) and a full-length 8.3 kbp Intracisternal A Particle genome (IAPE-Y), in a tail-to-tail organization. Although IAPs are encoded by a disperse multigene family (approximately 1000 copies per haploid genome), we present evidence that a significant proportion of the IAP-related sequences are present on the Y Chromosome (Chr) and that a >25 kbp genomic sequence, which contains the two proviral genomes, has been amplified on the Y Chr. Two discrete amplified families of MuRVY retroviral genomes distinguishable by a polymorphic restriction site were detected, suggestive that amplification occurred in incremental stages. The presence of MuRVY-related DNA sequences, but absence of IAPE-Y-related DNA sequences in Mus spretus suggests that the IAPE-Y retrotransposition event occurred after the evolutionary divergence of the lineages leading to Mus musculus and Mus spretus, and that the amplification of MuRVY occurred independently in the two lineages.

Infectivity of a Cryptosporidium species isolated from a domestic cat (Felis domestica) in lambs and mice

Two neonatal lambs were inoculated orally with purified Cryptosporidium species oocysts isolated from a farm cat. Oocysts first appeared in the faeces of the two lambs three and 10 days after infection. Two distinct sizes of oocysts were observed in the faeces of both the cat and the lambs, the smaller measuring approximately 5.0 x 4.5 microns and the larger measuring approximately 6.0 x 5.0 microns in diameter. The smaller type predominated. Histological examination of the alimentary tract of the lambs revealed endogenous stages of Cryptosporidium in the epithelial borders of the ileum. In addition, Cryptosporidium oocysts were detected in impression smears from the jejunum, ileum, caecum and colon. Suspensions of 10(3) oocysts from the faeces of the farm cat were inoculated into each of 10 newborn mice and 10(4) oocysts from the two experimentally infected lambs were inoculated into each of 20 newborn mice. Cryptosporidium oocysts were detected in gut homogenates from 19 of the 20 mice inoculated with oocysts from the lambs but in none of the mice inoculated with oocysts from the cat.

Formation of the ferritin iron mineral occurs in plastids

Ferritin in plants is a nuclear-encoded, multisubunit protein found in plastids; an N-terminal transit peptide targets the protein to the plastid, but the site for formation of the ferritin Fe mineral is unknown. In biology, ferritin is required to concentrate Fe to levels needed by cells (approximately 10(-7) M), far above the solubility of the free ion (10(-18) M); the protein directs the reversible phase transition of the hydrated metal ion in solution to hydrated Fe-oxo mineral. Low phosphate characterizes the solid-phase Fe mineral in the center of ferritin of the cytosolic animal ferritin, but high phosphate is the hallmark of Fe mineral in prokaryotic ferritin and plant (pea [Pisum sativum L.] seed) ferritin. Earlier studies using x-ray absorption spectroscopy showed that high concentrations of phosphate present during ferritin mineralization in vivo altered the local structure of Fe in the ferritin mineral so that it mimicked the prokaryotic type, whether the protein was from animals or bacteria. The use of x-ray absorption spectroscopy to analyze the Fe environment in pea-seed ferritin now shows that the natural ferritin mineral in plants has an Fe-P interaction at 3.26A, similar to that of bacterial ferritin; phosphate also prevented formation of the longer Fe-Fe interactions at 3.5A found in animal ferritins or in pea-seed ferritin reconstituted without phosphate. Such results indicate that ferritin mineralization occurs in the plastid, where the phosphate content is higher; a corollary is the existence of a plastid Fe uptake system to allow the concentration of Fe in the ferritin mineral.

Causes of suppurative keratitis in Ghana

AIMS

Suppurative keratitis is a serious problem in all tropical countries, but very little information is available about the causative organisms in Africa. The objectives were to identify the causative organisms and the proportion of cases caused by fungi in southern Ghana, and to determine whether correct decisions about treatment could be made on the basis of Gram stain in the eye clinic.

METHODS

Scrapings were taken from corneal ulcers of consecutive new patients presenting at Korle Bu Hospital, Accra, and inoculated on 'chocolate' and Sabouraud's agars. Further scrapings were taken for Gram staining and interpretation in the eye clinic. Duplicate slides were assessed by an experienced microbiologist in the UK.

RESULTS

One or more organisms were cultured from 114 of 199 patients (57.3%), the most common being Fusarium species, Pseudomonas aeruginosa, and Staphylococcus epidermidis. Fungi, alone or in combination, were isolated from 56% of the patients who had positive cultures. In total, 122 patients (61.3%) had their treatment either determined or altered based on the results of the microbiological diagnosis; in 87 of these solely on the basis of direct microscopic examination.

CONCLUSIONS

Infection by filamentous fungi accounted for more than half of the ulcers from which cultures were obtained. Both training in technique and experience in interpretation are necessary for microscopy based diagnosis by staff in the clinic to be of greatest value. Direct microscopy was particularly useful for detecting fungi.

The Sry-related HMG box-containing gene Sox6 is expressed in the adult testis and developing nervous system of the mouse

We have cloned and sequenced a full-length cDNA for the HMG box-containing, SRY-related gene Sox6 from mouse. The deduced protein sequence of Sox6 has considerable homology with that of the previously determined Sox5 sequence. It seems likely that these genes have diverged more recently than other members of the SOX gene family, although the two genes map to different chromosomes in the mouse. In common with Sox5, Sox6 is highly expressed in the adult mouse testis and the HMG domains of both proteins bind to the sequence 5'-AACAAT-3'. This suggests that the two genes may have overlapping functions in the regulation of gene expression during spermatogenesis in the adult mouse. However, Sox6 may have an additional role in the mouse embryo, where it is specifically expressed in the developing nervous system.